Better MPG with Autozone 10w-40 SL

[glxpassat]

I've been doing some short oci's with different synthetic oils because I've been trying to figure out if my oil pump was going bad or clogged up. Turns out it was a bad sending unit... Anyway, in the last 6 months these are what I've tried and my average mpg with each oil.

Syntec 5w-40 SL 27.7
Royal Purple 15w-40 SL 28.0
Mobil 1 15w-50 SM 27.5

I decided to add one pint of MMO to my 6 quarts of 15w-50 for a few miles to see if that would help my oil pressure in case the screen was sludged. I thought the MMO might thin the oil, but I didn't detect any change in oil pressure with it in the crankcase, not sure why... My average MPG did go up to 28.0, so MMO must be some slick stuff. I pulled the plug and bought some AZ 10w-40 SL to rinse out the MMO. I didn't change the oil filter, but was planning to when I dumped the AZ oil.

Now my average mpg is 29.2 and I don't want to let it out! Nothing else has change that could account for the increase. Maybe conventional has better ring seal? Maybe the MMO is magic? Anyone know anything about the AZ oils, I may just run this stuff all the time!

 

[TeeDub]

Maybe the cheap dino 10w-40 has already sheared down to a 30wt??? That would do it!

FWIW I'd run a 0w-30 Synth. In this motor and not the thick stuff.

 

[glxpassat]

It's only been in my motor for a few hundred miles, since last Saturday, so I doubt it's sheared yet. I did notice that the motor seemed more smooth and quite with the AZ oil as well. I used green GC for quite a few miles and it was giving me high lead readings so I've switched to 40w.

 

[glxpassat]

Also, my hot oil pressure hasn't changed so I know it hasn't sheared yet.

 

[wavinwayne]

Curious - what is the price per quart of the AZ oil?

 

[glxpassat]

I bought a 5 quart jug for $10.99.

 

[Cutehumor]

is this oil slotted price wise under valucraft or over valucraft?

 

[glxpassat]

I don't know, I've never looked at valuecraft before. After searching for a while, it seems this oil is made by Warren Unilube that makes Coastal products. So I went to their website, and here's their blurb, sounds like a decent oil. It definitly has surprised me although I haven't looked at any uoa's yet-

"Coastal Premium Motor Oils are superior-quality, high detergent automotive engine oils specially formulated to meet the stringent lubrication requirements of today's engines. High-viscosity-index base oils combine with a carefully selected additive package to provide maximum protection against wear, rust, corrosion, oxidative thickening, acid formation, sludge, and varnish deposits.

Coastal Premium Motor Oils meet or exceed the requirements of API Service SL, MIL-L-46152E, Ford M2C153E, GM-6048M, and 6049M.

Coastal Premium Motor Oils also give excellent performance in engines operating on LPG fuel."

 

[demarpaint]

It must be old stock since it is SL rated? Not that its a bad thing!

Frank D

 

[glxpassat]

No, Coastal shows on their site that the hd30, hd40, 10w40 and 20w50 are SL. That's why I chose to use it, as VW is sticking pretty close to SL specs in most of the oils they approve. All the other weights are SM.

http://www.warrenunilube.com/motoroils.html

 

[demarpaint]

Interesting, I am not familiar with the product, but it sounds like its working for you. Continue using it and see if the increased MPG continues for you. Even the slightest gains add up over time.

Frank D

 

[glxpassat]

Found one uoa on their 5w-30 and it was a good report with high fuel dilution - here

 

[ziggy]

Few years ago, i used a pint of MMO in my 95 neon. Forget what oil i used. 5w 30. I did immediatly notice, much better acceleration and engine response! So much in so, DEF a blind man would recognize it. I havnt used it since, becuase i preffer to use oil, not a chemcial multi purpose substitute. I cant say about the long run of it. I used a quart of Rislone year ago...engine was okay until after a few hundred miles, and developed BAD piston slap. OIl change after rislone, engien ran normal again.

 

[Merkava_4]

Contrary to popular belief, 10W-40 does have its place in some engines. Thin oils don't always give you the best fuel mileage; it's the oil that provides the best lubrication for a particular engine that gives the best fuel mileage. I feel sorry for all the engines out there that are in desperate need of a 10W-40 but the owner insists on 5W-30.

 

[Gannet167]

What's MMO?

 

[Cup of Joe]

Marvel Mystery Oil

 

[Gannet167]

MMO, isn't that an $8 bottle of kerosene?

 

[TeeDub]

A word of warning ... If you add MMO to some of the Amsoil chemistries it will turn to hydrocarbon jello. I spoke to someone locally (worked at an AZ store), who thought he'd "improve" the Amsoil he was running with MMO - bad idea.

 

[glxpassat]

I didn't leave the MMO in for very long and didn't notice any jello coming out when I dumped the M1.